Add 21/8 and 18/20
1st number: 2 5/8, 2nd number: 18/20
21/8 + 18/20 is 141/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 20 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 8 × 5 = 40,
21/8 = 21 × 5/8 × 5 = 105/40 - Likewise, for the 2nd fraction, since 20 × 2 = 40,
18/20 = 18 × 2/20 × 2 = 36/40 - Add the two like fractions:
105/40 + 36/40 = 105 + 36/40 = 141/40 - So, 21/8 + 18/20 = 141/40
In mixed form: 321/40
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